Drawtwister



y 1960 J. E. BROMLEY 2,937,489

DRAWTWISTER Filed Dec. 16, 1957 2 Sheets-Sheet l F/ INVENTOR.

' JAMES E BRO/MLE Y ATTpRA/EY J. E. BROMLEY DRAWTWISTER May 24, 1960 2Sheets-Sheet 2 Filed Dec. 16, 1957 INVENTOR. JAMES E BRO/14L EV BY wfl/awfim ATTORNEYS United States Patent 2,937,489 DRAWTWISTER James E.Bromley, Pensacola, Fla., assignor to The Chemstrand Corporation,vDecatur, Ala., a corporation of Delaware Filed Dec. 16, 1957, Ser. No.702,889

2 Claims. (Cl. 57-90) This invention relates to an improvement intextile machinery and more particularly to an improvement in adrawtwister employed for drawing and twisting filamentary material suchas nylon or the like. It is particularly applicable to a drawtwister ofthe type manufactured by the Whitin Machine Works of Whitinsville,Massachusetts.

In the processing of filamentary material, a common operation performedon synthetic material such as continuous filament nylon and the like, isa drawing operation for orienting the molecules in the filaments andimparting tensile strength thereto. In one type of textile machinerysuch as drawtwisters the filamentary material is drawn in apredetermined ratio and subsequently twisted a selected amount to give atwisted-filamentary end product having the desired physical properties.

In a drawtwister such as referred to above, the drawing operation iscarried out between feed rolls and draw rolls in accordance with wellknown drawing or drafting principles and the speed ratio between thefeed and draw rolls is established in accordance with the stretch ratiodesired.

It has been found, however, that during the rotation of the shaft onwhich the feed rolls are posi-' such as nylon on the machine failed toproduce an end product having the desired uniform physical properties.For instance, the torsional vibration in the shaft interfered with thedrawing operation and produced drawn filaments which were not uniform incross-sectional area and denier. As can be understood, this lack offilament uniformity inhibited subsequent treatment of the filaments suchas dyeing wherein it was found that the dyed filaments tended to streak.

Accordingly, a primary object of this invention is to provide a new andnovel improvement on textile machinery such as drawtwisters and the likewhich are provided with components for performing a filament drawingoperation.

Another object of this invention is to provide a new and novelcombination of elements in a drawtwister which utilizes a flexiblecoupling so that the torsional vibration in the drawtwister shafting isreduced or sub stantially eliminated.

A further object of this invention is to provide a new and novelcoupling arrangement for flexibly coupling the feed roll shaft or shaftsof a drawtwister to its driving means for improving the quality anduniformity of synthetic filaments processed by the drawtwister.

This invention further contemplates the provision of a new and novelcoupling arrangement for a drawtwister "ice 2 of the type manufacturedby the Whitin Machine Works of Whitinsville, Massachusetts, whichrenders the drawtwister more 'eflicient in operation in the processingof synthetic filaments and which is of such hovel construction as to besimply and easily installed.

A still further object of this invention is to provide a new and novelcombination of a flexible coupling anda textile drawtwister whichpermits the installation of the flexible coupling without dismantling orremoving the shafts to be connected, which is inexpensive inconstruction, which'is capable of prolonged use without danger ofbreakdown, and which virtually eliminates 'torsional vibration in thefeed roll shaft or shafts of the drawtwister so that an end product ofuniform physical properties is produced.

Other objects and advantages of the invention will become apparent fromthe following description taken in connection with the accompanyingdrawing.

The objects of the invention are accomplished by providing a flexiblecoupling which is preferably, but not necessarily, of a specificconstruction to permit easy installation on the roll shafting of adrawtwister such as the drawtwister manufactured by the Whitin MachineWorks of Whitinsville, Massachusetts. In the preferred embodiment, theflexible coupling connects the driving shaft of the drawtwister to thefeed roll shaft or shafts so that torsional vibration which develops inthe feed roll shaft during operation of the apparatus is dampened oreliminated in the coupling. The specific coupling employed includes aresilient coupling member which is positioned 'in coupling relationshipwith the driving and feed roll shafts of the drawtwister, and means areprovided for connecting the end portions of the shafts to the resilientcoupling member. Clamping means are also provided for clamping thecouling member in the shaft coupling relationship.

The novel features which are believed to be characteristic of theinvention are set forth with particularity in the appended claims. Theinvention itself, however, both as to'its organization and method ofoperation may be best understood by reference to the followingdescription taken in conjunction with the accompanying drawing in which:

Figure 1 is a partial diagrammatic view of the drawtwister with'whichthis invention is incorporated;

Figure 2 is a partial view taken substantially along line 22 of Figure 1in the direction of the arrows;

Figure 3 is an enlarged view of a flexible coupling incorporated withthe apparatus of Figure 1;

Figure 4 is a sectional view taken substantially along line 44 of Figure3; and

Figure 5 is a sectional view taken substantially along line 5-5 ofFigure 4 in the direction of the arrows.

- Referring now to the drawing, there is shown in Figure 1 a drawtwisterof which this invention represents an improvement. This drawtwister isshown diagrammatically for the purpose of clarity and is preferably ofthe type manufactured by the Whitin Machine Works of Whitinsville,Massachusetts. As is well known, the drawtwister of Figure 1 is employedto draw and twist filamentary material for molecular orientation of thefilaments and to provide a twisted end product. In the particulardrawtwister referred to above a bracket or support 11 is providedcentrally of the machine and is arranged to support arms 12 whichaccommodate thread packages such as wound spin bobbins 13 or the like.As is well known, such a drawtwister may be used to drawtwist syntheticfilaments such as nylon and it is with reference to the drawtwisting ofnylon that the invention will be described hereinafter. Furthermore, itwill be noted that the bracket 11 is arranged to support spin bobbins 13on opposite sides of the machine in order to increase its capacity. Forthe purposes of simplicity and clarity the operation of one side of themachine only will be described hereinafter, but it should be understoodthat duplicate apparatus is positioned on each side of the drawtwister.Furthermore, it should be understood that on eachside of the machine aplurality of spin bobbins 13 are arranged according to the number ofindividual strands or threads tobe processed.

In the operation of the drawtwister of Figure 1, a thread 14, which hasbeen initially packaged on the spin bobbin 13 is unwound from the spinbobbin and carried through a snub guide 16 and a snubber 17 in adownward direction. The direction of the thread is then changed by meansof a traverse guide 18 so that it moves from the traverse guide 18upwardly behind a top or cot roll 19 pivotally mounted by means of anarm 21. By means of the pivotal arm 21 the top roll 19 may be moved intoengagement with a feed roll 22 so that the thread 14 may be heldtherebetween as it advances downwardly through the drawtwister.

The roll 22 as shown in Figure 2 is preferably an integral part of anelongated shaft 23 referred to generally as the feed roll shaft. Feedroll means including cooperating top and feed rolls 19, 22 are spacedlongitudinally of the shaft 23 and are of a selected number so as tocorrespond to the number of threads 14 processed by the drawtwister. Thefeed roll shaft 23 is supported, as shown inFigure 2, by any suitablemeans such as bearings 24, and is arranged to be driven in a mannerdescribed hereinafter.

The thread 14 advancing from the feed roll 22 moves around a draw pin 26and is wrapped or laced a multiple number of turns around a separatorpin 27 and draw roll 28. The draw roll 28 is rotatably mounted on ashaft 29 and is driven by any suitable means (not shown) a portion ofwhich is contained within a housing 31. As is well known, the draw roll28 which is rotated at a selected higher speed than the feed roll shaft23 im-' poses a drawing or stretching action on the thread 14 so thatthe filament or filaments are stretched at the draw pin 26 and themolecules in the thread filaments are oriented.

Subsequent to this stretching or drawing operation, the thread advancesthrough a balloon guide 32 and to a ring traveler 33 loosely mounted ona traveler ring 34. As is well known, the traveler ring 34 is arrangedto be moved vertically in a reciprocating manner by means of a lay rail36 while the thread 14 is wound in a twisted manner on a bobbin 37supported on a spindle 38 suitably driven by means such as a belt 39.Thus, the nylon thread 14 is wound in a drawn and twisted manner on thebobbin 37 in a packaged form.

In the drawtwisting of synthetic filaments such as nylon, it has beenfound that the feed roll shaft 23 is subject to considerable torsionalvibration due to many factors such as bearing drag, high shaftflexibility, and the like. Furthermore, it was found that as a result ofthis torsional vibration the thread 14 was not drawn properly at thedraw pin 26 with the result that uniform filament diameter was notobtained and erratic denier resulted in the thread 14. This is highlyobjectionable particularly where the thread is subjected to a subsequentdye operation as dye streaks appeared in the thread filaments.

Means, therefore, have been provided with this invention for reducing orsubstantially eliminating this feed roll shaft torsional vibration. Morespecifically, the feed roll shaft 23 on each side of the machine isconnected at one end to driving means, designated generally by thenumeral 40, by means of a flexible coupling designated generally by thenumeral 41. Any suitable type of driving means may be employed andpreferably relatively short driving shafts 42 are arranged in coaxialalignment with the ends of the feed roll shafts so that they may beconnected thereto by means of the coupling 41. These driving shafts 42which may be supported .within suitable bearing means 43 are driven bymeans of bevel gears 44 connected as shown to a main drive shaft 46. Bymeans such as spur gears 47 connected to a suitable source of power (notshown) the main drive shaft 46 is rotated to drive the pair of feed rollshafts 23 shown in Figure 2 simultaneously and at the same speed.

While it should be understood that any suitable type of flexiblecoupling may be provided for dampening or eliminating the torsionalvibration in the feed roll shafts 23, there is shown in Figures 3-5 aflexible coupling which is preferably incorporated with the illustrateddrawtwister. This flexible coupling, which has been designated by thenumeral 41, is arranged in a manner, as will be obvious in theexplanation to follow, to drivably couple the feed roll shaft 23 to thedriving shaft 42.

In order to connect the shafts 23, 42, in driving engagement, aresilient coupling member 48 is positioned in coupling relationship withthe opposed ends of the shafts. Although a tubular form may be employed,the coupling member 48 is preferably fabricated in planar form and issubsequently wrapped in circumferentially extending relationship withthe ends of the shafts as shown in- Figures 3-5.

Means are provided for connecting the shafts to this resilient sleevemember which in the preferred embodiment comprises a pair of keys 49, 50which are positioned within longitudinally aligned recesses 51, 52,respectively, in the resilient sleeve member 48. These keys 49, 50 arealso arranged to be inserted within corresponding recesses 53, 54 in theshafts 42, 23, respectively, when the shafts have been rotated into theproper angular relationship.

Means are provided for clamping the resilient sleeve member 48 in theassembled position illustrated which include a pair of hemisphericalhalf-shells 55, 56, arranged to cooperate in complementary relationshipto form a tubular clamp. The half-shells 55, 56 are clamped in theclamping position by any suitable means such as a plurality of bolts 57arranged on diametrically opposite sides of the half-shells andpreferably in an inverted relationship for positive clamping action.

Although the sleeve member 48 may be dimensioned so as to form a closedcylindrical member in the assembled position, it is preferably shortenedso that its opposed ends define a space 58 for accommodating alongitudinally extending key 59 located partially within a recess 60 inthe inner wall of the upper half-shell as shown best in Figure 4. Bymeans of this key 59, relative motion between the complementaryhalf-shells 55, 56 and the sleeve member 48 is prevented.

It can be seen that by means of this invention a coupling arrangementhas been provided for the feed roll shafts of a drawtwister of the typeillustrated and described above which enables the drawing or stretchingoperation of the filamentary threads to be carried out in a relativelyvibrationless manner. The feed roll shafts may, therefore, be rotated ata uniform speed so that the thread advancing therethrough moves at arelatively constant speed. Any tendency of the feed roll shaft tovibrate torsionally would be dampened by the resilient sleeve member ofthe flexible coupling acting in shear. Drawtwisted thread whichheretofore was characterized by erratic physical properties may now bedrawn and subsequently twisted so that filaments of uniform denier andsuperior dyeing characteristics are produced. Furthermore, the couplingemployed as described with the drawtwister is rugged in construction andwill sustain high acceleration and deceleration rates whiletransmitting'a relatively heavy torque. In addition, the couplingdescribed may be installed quickly or readily repaired without removingor disassembling the associated parts of the equipment.

While there has been described what at present is considered to be thepreferred embodiment of the invention, it will be understood by thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention, and, therefore, it is theaim of the appended claims to cover all such changes and modificationsas fall within the true spirit and scope of the invention.

1. A drawtwister for drawing and twisting filamentary materialcomprising, in combination, a feed roll shaft rotatably mounted on saiddrawtwister, feed roll means on said shaft, means for driving said feedroll shaft including a driving shaft, a flexible coupling for drivablycoupling said driving shaft to said feed roll shaft, and draw roll meansrotatably mounted on said drawtwister and positioned to receive thefilamentary material from said feed roll means, said flexible couplingincluding a Having thus described the invention, what is claimed a 10half-shells arranged to form a tubular clamp concentric to be positionedin encircling relationship with the end portions of said driving andfeed rollshafts when said end portions are positioned in substantiallycoaxial endwise relationship, means for connecting each of said shaftend portions to said sheet material, and means for clamping said sheetmaterial to the end portions of said shafts.

2. A drawtwister in accordance with claim 1 wherein said clamping meanscomprise a pair of complementary with said sheet material and means forfixedly securing said assembled half-shells in said clamping engagement.

2,479,278 2,514,634 Galbreath July 11, 1950 2,739,462 Wincenciak Mar.27, 1956

